Hello!

I have a few questions about protein structures and denaturing agents!

1. I know that the hydrogen bonds between the oxygen from the carbonyl group of one amino acid and the hydrogen from the amino group from another amino acid, are responsible for stabilizing and creating a protein's secondary structure. However, we also learned that, ionic interactions, hydrophobic interactions, Van der Waal forces are found in the secondary structure as well. Do I follow the logic that these forces simply exist in the secondary structure, but not contribute to its stability as much as hydrogen bonds (as R groups are not involved in determining secondary structure)?

2. pH and salt are denaturing agents, that disrupt electrostatic interactions; which to my understanding would include hydrogen bonds, ionic bonds and Van der Waal forces. Would they also disrupt covalent bonds, and if so - which covalent bonds?

Thank you so much!